[femm] Re: magnetic launcher

[mathewsd@xxxxxxxxxxxxx]

If you are going to levitate something, Maglifter may be the way to go.
If you are going to shoot something, say to the moon, you need a
railgun or one of its variants. You should use railgun (or rail gun)
as a keyword in searching for information. Maxwell Laboratories in San
Diego builds these. The university at Austin, Texas (U. of Texas?,
Texas Tech?) is very active in this area. The way a railgun works is
this: A conducting loop wants to expand the area it encloses when you
pass a direct current through it, so you hold two sides (rails, coat
hangers, etc.) fixed and use your metallic projectile as a
freely-moving end piece. You start your projectile (paper clip) near
one end, let it pick up speed as it goes along the rails, and have it
go off the far end. When you hook your dc source at the near end,
i.e. near the starting point, the "loop" expands and sends the
projectile flying. Since dc power supplies don't like to see short
circuits, you actually charge up a big capacitor and attach it through
a small resistor to the rails. Yes, you can build a coil version, but
rails are better mechanically when large forces are involved.